Device for clamping together pieces of sheet material to facilitate riveting and the like operations



Jim. 30, 1940. A VERDON.RQE 2,188,450

DEVICE FOR CLAIPING TOGETHER PIECES 0F SHEET MATERIAL To EACILITATERIVETING ANDTHE LIKE OPERATIONS Filed ay 10)1938 Illlll Patented Jas.30, 1940 UNITED STATE DEVICE Eon CLAMPING TOGETHER PIECE oF snEETMATERIAL To FAoILITATE RIVETING AND THE LIKE orEnATIoNs AlliottVerdon-Roe, Southampton, England, as-

signor to Aviation4 Developments Limited, London, England, a joint-stockcompany of England Application May l0, 1938, Serial No. 207,172 In GreatBritain Ma'y 14, '1937 6 Claims.

The present invention refers to improved devices for clamping togetherpieces of sheet material, especially to facilitate riveting and the likeoperations.

When light metal sheets have to be riveted together the hitherto usualpractice is to use ordinary bolts and nuts for securing the sheetstogether and much time is lost in threading the. nuts on the bolts,especially in the case of closed structures such as the hull of a flyingboat or the fuselage or wing of an aeroplane of the kind having Va metalskin. In such an operation a second person is usually required to threadthe nuts on the bolts and the operation frequently presents greatdiiculty, e. g., in awkwardly placed corners, and in some cases theinside end of the bolt may be completely inaccessible. The presentinvention affords a means by which one person can quickly clamp sheetstogether using only one hand and without the aid of any tools.

The improved device according to the present invention comprises aninternally threaded tubular member, a claw member externally threadedfor engagement with -the internally threaded tubular member and anapertured vabutmentmember, through which the claw member passes, beingslidable and non-rotatable therein, and which is rotatablyl andnon-slidably retained on one end of the tubular member.

Preferably the abutment member is provided with a central projectingspigot (adapted to enter an aperture inthe workpieces) said spigot beingapertured .to allow the claw member to pass' through it.

By relatively rotating the tubular member and the abutment member theclaw member is ex'- tended or is withdrawnfrom the abutment memberaccording to the direction of rotation. In

using the device the abutment and tubular members are rotated until theclaw is extended to a distance depending on the number and thickness ofsheets to be riveted together. The claw is then inserted in a holepassing through all the .sheets until its claw end is clear of the innerface of the inner sheet. The abutment memberv 'being against the outerface of the outer sheet, the tubular member is screwed in the directionto withdraw the claw and cause it to engage the inner sheet; furtherrotation of the tubular member causes all the sheets to be clampedtogether.`

The provision of a spigot on the outer face of the abutment memberensures that the device is suiciently centralised with respect to'thehole in the sheets to prevent the claw end from slipping back throughthe hole when the claw member is retracted to tighten the device.

In a preferred form of construction the shank of the clawmember is fiatand passes through a prevent free rotation of the tubular member in slotin the abutment member to prevent relative movement of these parts.

Preferably also one end of the internally threaded tubular member isoutwardly iianged and is embraced by the abutment member which iscup-shaped and has its free edge loosely closed,

-in over the flanged end of the tubular member to retain it thereonwhile allowing it to turn.

It is further advantageous to provide the abutment member with a ring ofrubber o ra like or the surface of the workpiece will be marked by theabutment member. v

The present invention and a manner of performing the same will be morefully understood from the following description of an embodiment of theinvention having reference to the accompanying drawing, in which: I

Fig. 1 is a View in elevation of the device assembled. f

Fig. 2 is an exploded view of the same, in side elevation,'partly insection, the parts being separated from one another.

Fig. 3 is a sectional view taken along the line 3-3 of Fig. l. Y

Fig. 4 is a plan view of the showing of Fig. l.

Referring to thev drawing:

A tubular member 5 internally threaded at 6 is provided with a flange -1presenting a shoulder s'where it joins the main body of the member,which is of lesser diameter. 'I'he claw member comprises an externally4threaded part I0 engageable in the thread 6 of the tubular part 5 and aflattened shank II terminating in a claw l2. The abutment member is ofcupshaped form comprising a .disc I3 and a skirt I4. In the centre ofthe face of thedisc part I3 is a vspigot I5 and a slot I6 is formedthrough the` spigot and the disc part I3 so that the spigot isconstituted by two half-round parts as shown in Fig. 4. The device isassembled by inserting the shankll of the claw member through the slotI6 of the abutment member which is then seated on the end of the tubularmember 5 so that the skirt I4 of the abutment member surrounds theflange 1. The free edge I 4b of the skirt I4 is then spun or pressed inover the shoulder 8 of the ange 1 so as to retain the abutment theabutment member and to assist this lthe shoulder 8 should be formed witha generous radius.

It may be noted that the slot I6 must be long enough to allow the shank'II of the claw member to pass through it. If the slot I6 is locatedcentrally oi' the abutment member and the claw I2 extends slightly toone side as shownfthe tip of the claw I2 will overlap the end of theslot I6 when the claw member is withdrawn into the barrel of the tubularmember, thus limiting the inward movement of the claw member andpreventing it from being lost by being screwed out of the other end ofthe tubular member.

To enable the abutment member to obtain a good grip on the surface ofthe sheet against which it abuts an annular groove is formed in the discpart I3.oi' the abutment member and in this groove is inserted` a rubberring I1. In the embodiment illustrated the rubber ring I'I is oftrapezoidal section, the base being wider than the top part so that itis irmly retained inthe annular groove. This however is not essentialand a ring of rectangular section may be employed as an alternative.

Alternatively again, as hereinbefore stated, the rubber ring I'I may beomitted andthe face of the disc part IS milled or otherwise roughenedout of sheet metal, in which case the part I0 will 0 4 the thread 8. ofthe tubular member by a secnot present a continuous thread -but twoopposed sets of teeth, which after the flrst pressing operation'resemble the teeth of a saw, being given the required angle tocooperate with ond pressing operation performed in a die.

In using the device as illustrated the spigot Il is inserted ina holedrilled through the sheets to'be clamped sothat 'the claw I2 enters thehole. 'I'he abutment member is then held up against the outer sheet` andthe tubular member l rotated by means of the knurled end '9 until theclaw I2 'engages behind the innermost sheet. The lmurled end 9 is thenrotated in the opposite directionuntil-the sheets are gripped tlrmlybetween the claw I2 andthe rubber ring I'I of the abutment member. Thesheets are now firmly heldtogether andthe operator has both hands freefor riveting or drilling further holes or such 'What I clai'm is:

1. A device for clamping together pieces of sheet material, for exampleto facilitate riveting, including an internallyk threaded tubularmember, a claw.member externally threaded forensagement with theinternally threaded tubular member and an apertured abutment member,through which the claw member passes being slidable and non-rotatabletherein, and which is rotatably and non-'slidably retained on one end ofthe tubular member and is provided with a central projecting spigot(adapted to enter an aperture in the workpieces), said spigot beingapertured to allow theclaw member to pass through it.

2. A device for clamping together pieces of sheet material, for exampleto facilitate riveting, including an internally threaded tubular member,an abutment member rotatably and non-slidably retained on one endthereof and having a slot therein, and a claw member having a partexternally threaded for engagement with the internally threaded tubularmember and a iat part traversing the slot of said abutment member, beingslidable but non-rotatable in said slot and terminating in a claw.

3. A device for clamping together sheet material, for example tofacilitate riveting, comprising an internally threaded. tubular member,a claw member having a hook-like claw at one end, an externally threadedpart for engagement with the internal thread of the tubular member andthe claw and the abutment members.

4. A device for clamping together sheet mai terial, -for example tofacilitate riveting, comprising an internally threaded tubular memberoutwardly flanged at one end, 4a claw meme ber having a hook-like clawat one end, an externally threaded part for engagement with the internalthread of the tubular member and having a non-circular shank between theclaw'and the threaded part, and a cup shaped abutment member having aslot through which passes the shank of the claw member, said slotengaging the shank to prevent relative rotation between the claw memberand the abutment member which latter ilts loosely over the flanged endof the tubular member, its free edge being closed in over said anged endto retain it swivelably thereon.

15. A .device for ,clamping -together sheet material, for example tofacilitate riveting, comprising an internally threaded tubular member, aclaw member having a hook-like claw at one end, an externally threadedpart for engagement with the internal thread of the tubular member andhaving a non-circular shank between the claw and the threaded part, andan abutment member swivelably secured to the tubular mem# ber and havinga slot through which passes the -shank of the claw member, said slotengaging the shank to prevent lrelative rotationv between the claw andabutment members and a ring of yielding friction material carried bysaid abut' ment member'to make contact with a workpiece.

8. A devicefor clamping together sheet material,` for example tofacilitate riveting, comprising an internally threaded tubular member, aclaw member having a hook-like claw at one end, an externallythreadedpart for engagement with the internal thread of the tubular member andhaving a noncircular shankgbetween the claw and the threaded part, anabutment member swivelably secured to the tubular member and having aslot through which passes the shank pf the claw member, said slotengaging the shank to prevent relative rotation between the claw and theabutment members and a spigot, adapted to enter an aperture in theworkpieces, mounted on the 'abutment member and apertured to allow the

